Cutting pliers

ABSTRACT

A pair of diagonal, wire cutting pliers are provided which include a pair of clipping gripping members resiliently secured to the cutting jaws of the pliers to retain clippings formed when a wire is cut by the pliers.

United States Patent 91 Makkay et a1.

[ CUTTING PLIERS [75] Inventors: Egon J. V. Makkay, New

Brunswick; John J. Pesce, Princeton, both of NJ.

[73] Assignee: RCA Corporation, New York, [22] Filed: Jan. 12, 1973 [21]Appl. No.: 323,022

Related US. Application Data [63] Continuation of Ser. No. 126,796,March 22, 1971,

abandoned.

[52] US. Cl. 30/124 [51] Int. Cl B26b 17/00 [58] Field of Search 30/124,134, 186, 30/191 [56] References Cited UNITED STATES PATENTS 2,323,4977/1943 Str out 30 124 41 ink 1 Oct. 9, 1973 8/1955 Liscomb 30/124 X3/1964 Popek 30/134 FOREIGN PATENTS OR APPLICATIONS 1,036,824 7/1966Great Britain 30/124 1,912,254 9/1970 Germany 1,443,560 7/1965 France30/124 Primary ExaminerJames L. Jones, Jr. Assistant ExaminerJ. C.Peters Att0rneyEdward J. Norton et a1.

3 Claims, 6 Drawing Figures CUTTING PLIERS This is a continuation ofapplication Ser. No. 126,796 filed Mar. 22,.1971, now abandoned.

BACKGROUNDOF THE INVENTION This invention relates to cutting pliers, andmore particularly, wire cutting pliers.

In the manufacture of electrical apparatus, it becomes necessary duringthe assembly of the apparatus to provide connections from variousterminal elements which include, in the case of printed circuits, theconnection of components to a printed circuit board. When the connectionor connections are completed, there is usually a superfluous end of thewire remaining. A frequent problem arises when the excessive wire endshave to be removed. Usually the wire erid is clipped with a pair ofcutting pliers. However, the clipped end may fly out with some danger tothe operator or may fly out and get lost among the electrical apparatuscomponents causing possible subsequent electrical failure. Therefore,these clippings must be removed to prevent them from becomingdetrimental to the piece of equipmentJl-IoWever the shorterthe lengthand diameter of the clipping, the more difficult it' is to retain untilan operator may properly discard it.

SUMMARY OF THE INVENTION In accordance with the present inventiongripping means are provided" for use witha wire cutting tool: Thecutting tool has a pair of pivotally mountedQabdttable cutting jaws, twofaces of each jaw being tapered to form a cuttingedge. One of the facesofeach jaw meets a corresponding face of the other jawforming an angulartrough therebetweenwhen the cutting edges are abutted. The grippingmeans includes a pairof gripping members made of thin springsheet metaland'each mountable on one of the jaws. Each member has a sharp,blade-like gripping edge adjacent and substantially parallel to thecutting edge of the jaw upon which it is-mounted. The gripping edge ofeach member is part of a face section closely spaced'from andsubstantially parallel to a tapered jaw face. A shoulder section dependsfrom'the face section and is shaped to form the inember to the shape ofthe jaw. A tab extends fromthe shoulder section. The tab of each'memberis fixedly secured to the corresponding one of the jaws so as toresiliently suspend'the face and shoulder sections from the respectivejaw.

IN THE DRAWING FIG. 1 is a plan view of a pair of pliers constructed inaccordance with the present invention.

FIG. 2 is a cross-sectional view through the jaws of the pliers ofFIG. 1. l

FIG. 3 is a-view similar to that of FIG. 2 showing the jaws of thepliers closed on a wire and'the clipped end of the wire restrained bythe gripping members of' the present invention.

FIGS. 4a and b are plan and side views, respectively, while FIG. 40 is abottom perspective view of one of the clamping members.

DETAILED DESCRIPTION In FIG. 1, a pair of conventional diagonalcuttingpliers are shown. A pair of gripping members 12 and 14 in accordancewith the present invention are mounted, respectively, on the cuttingjaws l3 and 15 of the pliers l0. Pliers 10 are illustrated to thatextent necessary to describe the present invention. Jaws l3 and 15 ofthe pliers 10 pivot about pivot pin 17 such that the cutting edges 28and 29 of the jaws when abutted will cut a wire disposed between thejaws. Only part"of the handles 20 and 21 are shown. A cross-sectionthrough the jaws of the pliers 10 along lines 2-2 in FIG. 1 isillustrated in FIG. 2. In FIG. 2, the pivot axis of jaws 13 and 15 isshown by arrow 23. The jaws l3 and 15 have faces 25 and 24,respectively, which are aligned with one another and second faces 27 and26 respectively, which taper toward faces 25 and 24 respectively to formcutting edges 29 and 28 on the respective jaws 13 and 15.

In a pair of pliers of the type illustrated, cutting is performed by theabutting sharpened edges 28 and 29. This cutting is in contradistinctionto cutting by apair of shears in which cutting is performed byadjacently sliding surfaces. When jaws l3 and 15 pivot about axis 23,cutting edges 28 and 29 move coplanar with respect to each other andnormal to the picot axis 23. Faces 26 and- 27 are inclined to faces 24and 25, respectively, to form an angular trough therebetween when thecutting edges are abutted. The angle of faces 26 and 27 is determined bythe strength and cutting characteristics designed for a pair ofindividual pliers. Faces 24 and 25 are substantially coplanar such thatthe pliers can be used to clip a wire as closely as possible fromwhatever the wire protrudes.

A pair of spring members 12 and 14 according to the presentinvention arepreferably made of stainless steel or othersimilar hard, tough, durablemetal and are formed as illustrated inthe Figures. FIG. 4 illustratesthe structure of member 12 which is a mirror image of member 14. Asillustrated, the members 12 and 14'are provided with face sections 30and 40,'shoulder sections 31 and 51 which depend, respectively, from theface sections and tabs 32 and 38 which depend, respectively, from theshoulder sections. Face sections 40 and 30 are formed generally to havethe same contour as each of the respective jaw faces 26 and 27 ofpliers'lfl'. The intersection of edge 33 and face section 30 forms thegripping edge 7 of member 12, while the intersection of edge 43'and facesection 40 forms the gripping edge 8 of member 14, the intersectionsbeing formed into sharp blade-like edges.

The face section 30 and shoulder section 31 of member 12 are elongatedin the general direction of jaw 13. Section 31 is elongated greater thansection 30 to form a tab 32 which depends from section 31 at junction 35which intersects longitudinal edges 34 and 39 bounding section 31. Tab32 is suitably bent at a slight angle to section 31 to permit member 12to conform to the outer surfaces of the corresponding jaw 13 as shown inFIG. 1. It is to be understood that junction 35 is proillustrated. Tab32 of the left hand member 12 and tab" 38 of the right hand member 14are each, respectively, secured to the corresponding jaws 13 and 15.Conventional means, preferably spot welding, may be used to secure thesetabs to the jaws. Face sections 30, 40 and shoulder sections 31, 51 ofmembers 12 and 14, respectively, are spaced closely adjacent the faces27 and 26 and edges 41 and 42, respectively, ofjaws 13 and of thepliers. Shoulders 31 and 51 are formed over the corresponding jawsparallel and closely spaced to edges 41, 42 of jaws 13 and 15. Thegripping edges 7 and 8 overhang slightly the cutting edges 29 and 28 ofthe jaws, when the jaws are in the open condition. When the jaws havethe cutting edges 29, 28 abutting in the closed condition, theoverhanging portions of each of the members causes the gripping edges 7and 8 of the members to be resiliently displaced from the position shownin FIG. 2.

As indicated above, members 12 and 14 are preferably stainless steel.Additionally, these members are provided with thin cross-sections, forexample, preferably 0.005 inches thick. As a result, edges 7 and 8 areprovided with hard, knife-like characteristics capable of withstandingrepetitive gripping actions without noticeable wear or loss of theknife-like characteristics. The advantage of these knife-likecharacteristics is that edges 7 and 8, even when slightly pressedagainst a clipping, will dig or scratch the clipping. This digging orscratching provides the gripping members with a stephold" grip on theclipping rather than merely a static surface friction grip as occurswhen one blunt surface is pressed against another blunt surface. When aclipping is thrust in the direction of arrow 23, the angle of attack offaces 30 and 40 with the clipping causes edges 7 and 8 to dig furtherinto the clipping, increasing the gripping action.

Resilient displacement of each of members 12 and 14 from their freeposition in a direction generally normal to arrow 23 by a wire insertedbetween edges 7 and 8 causes spring tension to be exerted on anyclipping by the members when the jaws are closed in the abuttingposition, thus providing pressure on edges 7 and 8 against the clipping.However, while edges 7 and 8 may be resiliently displaced in a directionnormal to arrow 23 to permit a wire to be inserted therebetween, the

configuration of the members prevents resilient displacement of edges 7and 8 in the direction of arrow 23 permitting the positive gripping of aclipping. That is, forces imparted to face sections 30 and 40 in thedirection of arrow 23 are transmitted to the junction of the tabs andcorresponding shoulder sections. The tabs and shoulder sections are notrotatable with respect to each other in the direction of arrow 23 atthese junctions therefore providing, resistance to any translation bythe members in direction 23. In addition, since the movement of edges 33and 43 of the members is limited to a direction generally normal toarrow 23, (jaws 13 and 15 prevent translation in direction opposite toarrow 23) insertion of a clipping or wire between these edges results ina slightly bowed condition in face sections 30 and 40. That is, thatportion of gripping edges 7 and 8 in direct contact with clipping aredisplaced in a direction opposite to arrow 23 with respect to theremainder of edges 7 and 8 not in contact with clipping 50 due to thetendency of the members to remain in their original position. This bowedcondition increases the angle of attack of face sections 30 and 40 withclipping 50 as seen in FIG. 3. This bowing condition provides additionalresistance to members 12 and 14 with respect to translation in thedirection of arrow 23 in opposition to thrusts by clipping 50 during thecutting action. Thus, the pair of thin resilient spring members inaccordance with the present invention are capable of providing highretention forces to a clipping in opposition to thrusts by the clippingin the direction of arrow 23. This combination of resiliency in onedirection, rigidity in the other direction, in addition to the diggingaction, provides an improved wire retaining plier.

FIG. 2 illustrates the normal position of members 12 and 14, while FIG.3 shows the position and displacement of gripping members 12 and 14 withthe jaws in the abutting closed condition and a wire clipping 50disposed between members 12 and 14. By providing aligned surfaces 24 and25 a wire clipping can be removed close to an object, for example, aprinted circuit board 60, from which the wire protrudes. In this case, awire 61 is shown protruding through an aperture 62 in board 60, the wirenot being connected to board 60. Pliers 10 have been used to clip theprotruding end 50 from the wire 61. End 50 is shown substantially in thesame relative position as it was just prior to being cut. This positionis maintained as a result of the opposed relationship between the twogripping edges 7 and 8 of members 12 and 14, which relationship providesequal and opposite forces to the clipped end 50, permitting the end 50to remain in substantially its original unclipped position.

The significance of maintaining the clipping 50 substantially in itsoriginal position is that components and other parts wired into aprinted circuit board may be operated on in the presoldered condition.In this condition the wires are usually loose. When the ends of thewires are clipped, the clipping action could bend the wire, and thus,move the components as well as the associated leads such as wire 61,disrupting the component and wiring arrangement. According to theinvention, since the clipped end is substantially in the same positionas it was before the clipping occurred, no motion is imparted by theclipping action to the component (not shown) or its lead 61, and thusrelatively little disturbance would be made to the arrangement ofunsoldered preset components on a printed circuit board. Further theclose proximity of face sections 30 and 40 of gripping members 12 and14, respectively, and therefore, gripping edges 7 and 8, to the cuttingedges 28 and 29 permit short clippings to be retained thereby.

Pliers constructed according to the present invention using 0.005 thickstainless steel members 12 and 14 have retained clippings as short as0.020 inches which length is a function of the spacing between faces 30and 40 and jaws 13 and 15 and the thickness of members 12 and 14. Suchsmall clippings were impossible to retain using prior art pliers. Thepresent invention is especially useful with very fine gauge wiring suchas 20 gauge or smaller wire. It is to be noted that each of grippingedges 7 and 8 of members 12 and 14 overlap cutting edges 29 and 28 ofjaws 13 and 15, respectively, thus insuring resilient compression ofeach of edges 7 and 8 against clipping 50.

The present invention is especially suitable for miniature diagonalcutting pliers having a face of approximately 0.3 inches wide. When thepliers are to be used in extremely narrow and hard to get at locations,the members 12 and 14 are fabricated to extend over the ends of thecutting jaws. The ends of the jaws and the gripping members securedthereto as described above are then ground flat as shown in FIG. 1.Thus, there is a gripping edge on each of members 12 and 14 adjacent tothe extreme end 70 of the pliers. This advantageously provides improvedplier flexibility.

The material from which gripping members 12 and 14 are made should besufficiently thin to be resilient, sufficiently thick to provide sharpgripping corners for digging into the clipped portion of the wire,sufficiently strong to prevent permanent deformation when spring loadedduring the use thereof, and sufficiently hard to prevent undue wear.

In the Figures, the thickness of the gripping members i is shownenlarged and out-of-scale to better illustrate the gripping edges 7 and8. In practice, the members are provided with relatively thinnercross-sections as described above.

What is claimed is:

l. Gripping means for use with a wire cutting tool, said tool having apair of pivotally mounted abuttable cutting jaws, two faces of each jawbeing tapered to form a cutting edge, one of the faces of each jawmeeting a corresponding face on the other jaw to form an angular troughtherebetween when the cutting edges are abutted, said gripping meanscomprising:

a pair of gripping members each member being mounted on a separate,different one of said jaws and made of thin spring sheet metal forgripping between said members a portion of a wire cut by the tool,

each member having a sharp-blade-like wire biting edge adjacent andsubstantially parallel to the cutting edge of the jaw upon which it ismounted, said biting edge being part of a face section closely spacedfrom and substantially parallel to a tapered jaw face, said memberfurther having a shoulder section shaped to form the member to the shapeof the jaw depending from said face section and a tab depending fromsaid shoulder section,

said tab of each of said members being fixedly secured to thecorresponding jaw for resiliently suspending said face and shouldersections from the respective jaw whereby said biting edges areresiliently suspended adjacent said cutting edges to grip a wiredisposed between the biting edges.

2. The tool of claim 1 wherein each of said biting edges overlap thecorresponding adjacent cutting edge when said jaws are open such thatsaid biting edges are resiliently displaced when the cutting edges arein the closed abutting condition.

3. The tool of claim 1 wherein said shoulder portion is substantiallyparallel to the pivot axis of said jaws, said tab extending from saidshoulder portion substantially parallel to said pivot axis such thatsaid shoulder and face sections resiliently pivot solely about thejunction of said tab and said shoulder.

1. Gripping means for use with a wire cutting tool, said tool having apair of pivotally mounted abuttable cutting jaws, two faces of each jawbeing tapered to form a cutting edge, one of the faces of each jawmeeting a corresponding face on the other jaw to form an angular troughtherebetween when the cutting edges are abutted, said gripping meanscomprising: a pair of gripping members each member being mounted on aseparate, different one of said jaws and made of thin spring sheet metalfor gripping between said members a portion of a wire cut by the tool,each member having a sharp-blade-Like wire biting edge adjacent andsubstantially parallel to the cutting edge of the jaw upon which it ismounted, said biting edge being part of a face section closely spacedfrom and substantially parallel to a tapered jaw face, said memberfurther having a shoulder section shaped to form the member to the shapeof the jaw depending from said face section and a tab depending fromsaid shoulder section, said tab of each of said members being fixedlysecured to the corresponding jaw for resiliently suspending said faceand shoulder sections from the respective jaw whereby said biting edgesare resiliently suspended adjacent said cutting edges to grip a wiredisposed between the biting edges.
 2. The tool of claim 1 wherein eachof said biting edges overlap the corresponding adjacent cutting edgewhen said jaws are open such that said biting edges are resilientlydisplaced when the cutting edges are in the closed abutting condition.3. The tool of claim 1 wherein said shoulder portion is substantiallyparallel to the pivot axis of said jaws, said tab extending from saidshoulder portion substantially parallel to said pivot axis such thatsaid shoulder and face sections resiliently pivot solely about thejunction of said tab and said shoulder.